Biological Science Working PapersCopyright (c) 2015 Fayetteville State University All rights reserved.http://digitalcommons.uncfsu.edu/bio_wp
Recent documents in Biological Science Working Papersen-usWed, 18 Nov 2015 17:25:10 PST3600Dinosaurs and pterosaurs in Greek and Roman art and literature? An investigation of young-earth creationist claimshttp://digitalcommons.uncfsu.edu/bio_wp/8
http://digitalcommons.uncfsu.edu/bio_wp/8Tue, 26 Nov 2013 13:55:57 PST
Many young-Earth creationist (YEC) authors claim that ancient Greek and Roman writings describe dinosaurs and pterosaurs, and that Greco-Roman art illustrates Mesozoic reptiles. Such claims are used as "evidence" against evolutionary theory in an attempt to cast doubt on the separation of humans and such animals by millions of years. However, examination of the Greco-Roman materials in question reveals that none of them actually depict Mesozoic reptiles. In descriptions of "dragons" (Greek drakōn; Latin draco) in Greco-Roman literature—which YEC authors claim are dinosaurs—coils and the epithets ophis, serpens, and anguis reveal that the ancient authors are describing snakes, often large constrictors. This is the case for the draco described by Pliny, Phrygian dragons described by Aelian, the Vatican Hill child-eater mentioned by Pliny, the Bagradas River dragon, the legendary dragons that Alexander the Great supposedly encountered, and dragons in Greek mythology. An alleged theropod dinosaur in the Nile Mosaic of Palestrina is a mammal, possibly an otter. An alleged dinosaur in a Pompeii fresco is a crocodile. Herodotus' description of winged snakes is anatomically incompatible with pterosaurs and possibly refers to cobras. Alleged pterosaurs on an Alexandrian coin are winged snakes. An alleged Etruscan pterosaur head sculpture depicts a mammal. Two alleged Tanystropheus in a Roman mosaic from Lydney Park, England are mythical sea monsters. These YEC claims now join the ranks of discredited "evidence" against evolutionary theory.
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Phil SenterDinodang: The Melon Rex Mythhttp://digitalcommons.uncfsu.edu/bio_wp/7
http://digitalcommons.uncfsu.edu/bio_wp/7Tue, 18 Sep 2012 12:15:17 PDTPhilip J. SenterEvidence for a sauropod−like metacarpal configuration in stegosaurian dinosaurshttp://digitalcommons.uncfsu.edu/bio_wp/6
http://digitalcommons.uncfsu.edu/bio_wp/6Tue, 18 Sep 2012 12:15:16 PDT
The stegosaurian forelimb is usually portrayed with the metacarpals slanted and distally spread. However, manual manipulation of stegosaurian metacarpals reveals that in that configuration they do not articulate with each other nor with the rest of the forelimb. Rather, they do articulate with each other and with the rest of the forelimb when posed vertically and arranged in a compact, semi−tubular configuration, as in sauropods. This configuration agrees with data from articulated specimens and trackways. As with sauropods, this metacarpal configuration makes retention of phalanges awkward for locomotion and may be functionally related to the vestigiality of the manual phalanges of the outer digits.
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Philip J. SenterEvidence for a sauropod−like metacarpal configuration in ankylosaurian dinosaurshttp://digitalcommons.uncfsu.edu/bio_wp/5
http://digitalcommons.uncfsu.edu/bio_wp/5Tue, 18 Sep 2012 12:15:15 PDTAnkylosaurian dinosaurs are armored, quadrupedal members of the ornithischian clade Thyreophora. Ankylosaurs are typically portrayed with the metacarpals slanted and distally divergent, with their proximal ends arranged in a shallow arc, both in the literature (Matthew 1922; Gaston et al. 2001; McCrea et al. 2001; Vickaryous et al. 2004) and in museum mounts (Fig. 1). In contrast, Carpenter (1984) illustrated the metacarpals of the ankylosaur Sauropelta edwardsorum Ostrom, 1970, from the Lower Cretaceous Cloverly Formation of Wyoming and Montana, with their proximal ends arranged in a tight, semicircular arc, but even in that depiction themetacarpals were slanted and distally divergent. Members of the thyreophoran clade Stegosauria, the sister taxon to the Ankylosauria (Butler et al. 2008), have also typically been portrayed with slanted and distally divergent metacarpals (Marsh 1891; Gilmore 1914; Galton and Upchurch 2004). Some researchers expressed the opinion that stegosaur metacarpals were held vertically, not distally divergent, with their proximal ends arranged in a tight, semicircular arc, so that the metacarpus formed a vertical half−tube (von Huene 1931; Thulborn 1990; Christiansen 1997) such that flexion of digit I would move it toward digit V. Manual manipulation of stegosaurian metacarpals has since confirmed that this is the correct configuration of the stegosaurian metacarpus (Senter 2010).Here I investigate the possibility that the ankylosaurian metacarpus exhibited a similar configuration. As in the previous study on stegosaurs (Senter 2010), I treat the slanting and spreading configuration and the vertical semi−tubular configuration as competing hypotheses, each with a set of testable predictions. Each hypothesis of metacarpal configuration in ankylosaurs predicts that the configuration (1) is allowed by the shapes of the metacarpals, (2) provides a better fit (alignment and contact of opposing articular surfaces) between the metacarpals than the competing hypothesis, (3) does not compromise the goodness of fit between the metacarpals and the phalanges, (4) is not contradicted by articulated specimens, and (5) agrees with ichnological evidence. In the previous study on stegosaurs I included an additional prediction: that the configuration provides sufficient support for and does not disarticulate the more proximal forelimb bones. Here, that prediction is omitted, because the ankylosaurian carpus is unknown (Vickaryous et al. 2004) except for a single carpal described by Maleev (1954).
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Philip J. SenterVestigial structures in the appendicular skeletons of eight African skink species (Squamata, Scincidae)http://digitalcommons.uncfsu.edu/bio_wp/4
http://digitalcommons.uncfsu.edu/bio_wp/4Tue, 18 Sep 2012 12:15:14 PDT
Limb reduction and loss, with reduction of limb and girdle skeletons to a vestigial state, has occurred several times independently within the skink family (Scincidae). The vestigial appendicular skeletons of most limbless skinks have not been described before now. Here we describe those of eight African skink species, all with a burrowing lifestyle: Acontias percivali, Acontias meleagris, Typhlosaurus cregoi, Typhlosaurus lineatus, Typhlacontias gracilis, Sepsina bayonii, Scelotes anguina and Scelotes arenicola. For all but two (A. meleagris and Sc. arenicola) the appendicular skeletons were previously undescribed. Limbs are absent in all specimens except for vestigial hindlimbs in Se. bayonii and vestigial femurs in one specimen of Sc. arenicola. In our sample, the pectoral girdle is reduced to a pair of tiny slivers in A. percivali, Ty. gracilis, Se. bayonii and Sc. anguina. It is absent in the other specimens. The pelvic girdle is absent in Ty. cregoi. In all the rest but Se. bayonii it is vestigial, retaining only the ilium in A. meleagris, Ty. lineatus and one specimen of Sc. arenicola. This study adds to the number of skink species with vestigial appendicular skeletons that have been described. It also adds to the rangeof documented intraspecific variation in the vestigial appendicular skeletons of A. meleagris, Sc. arenicola and the Australian skinks Lerista stylis and Lerista carpentariae. We observed asymmetry between the left and right sides in the vestigial appendicular skeletons of four of the African skink species: A. meleagris, Sc. anguina, Sc. arenicola and Se. bayonii
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J. G. Moch et al.New Dromaeosaurids (Dinosauria: Theropoda) from the Lower Cretaceous of Utah, and the Evolution of the Dromaeosaurid Tailhttp://digitalcommons.uncfsu.edu/bio_wp/3
http://digitalcommons.uncfsu.edu/bio_wp/3Tue, 18 Sep 2012 12:15:12 PDT
Background: The Yellow Cat Member of the Cedar Mountain Formation (Early Cretaceous, Barremian? – Aptian) of Utah has yielded a rich theropod fauna, including the coelurosaur Nedcolbertia justinhofmanni, the therizinosauroid Falcarius utahensis, the troodontid Geminiraptor suarezarum, and the dromaeosaurid Utahraptor ostrommaysorum. Recent excavation has uncovered three new dromaeosaurid specimens. One specimen, which we designate the holotype of the new genus and species Yurgovuchia doellingi, is represented by a partial axial skeleton and a partial left pubis. A second specimen consists of a right pubis and a possibly associated radius. The third specimen consists of a tail skeleton that is unique among known Cedar Mountain dromaeosaurids.

Methodology/Principal Findings: Y. doellingi resembles Utahraptor ostrommaysorum in that its caudal prezygapophyses are elongated but not to the degree present in most dromaeosaurids. The specimen represented by the right pubis exhibits a pronounced pubic tubercle, a velociraptorine trait that is absent in Y. doellingi. The specimen represented by the tail skeleton exhibits the extreme elongation of the caudal prezygapophyses that is typical of most dromaeosaurids. Here we perform a phylogenetic analysis to determine the phylogenetic position of Y. doellingi. Using the resulting phylogeny as a framework, we trace changes in character states of the tail across Coelurosauria to elucidate the evolution of the dromaeosaurid tail.

Conclusions/Significance: The new specimens add to the known diversity of Dromaeosauridae and to the known diversity within the Yellow Cat paleofauna. Phylogenetic analysis places Y. doellingi in a clade with Utahraptor, Achillobator, and Dromaeosaurus. Character state distribution indicates that the presence of intermediate-length caudal prezygapophyses in that clade is not an evolutionarily precursor to extreme prezygapophyseal elongation but represents a secondary shortening of caudal prezygapophyses. It appears to represent part of a trend within Dromaeosauridae that couples an increase in tail flexibility with increasing size.

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Philip J. Senter et al.More “dinosaur” and “pterosaur” rock art that isn’thttp://digitalcommons.uncfsu.edu/bio_wp/2
http://digitalcommons.uncfsu.edu/bio_wp/2Tue, 18 Sep 2012 12:15:11 PDT
To support claims of the coexistence of humans with dinosaurs and pterosaurs, young-earth creationist authors have identified several pieces of ancient rock art as depictions of dinosaurs or pterosaurs. Here, nine such claims are investigated. An alleged pterosaur painting in Black Dragon Canyon, Utah, is actually not a single painting. Its “head” and “neck” are a painting of a person with outstretched arms. Its torso and limbs are those of a painting of a second person with outstretched arms, whose body continues into the “pterosaur’s” “wing.” The other “wing” is a painting of a horned serpent. The three paintings only appear connected because someone outlined the group with chalk. An alleged dinosaur petroglyph in Havasupai Canyon, Arizona, is a stylized bird with an extension on one foot; the hooked line that represents its head and neck is a stylized bird head. A second alleged dinosaur petroglyph in Havasupai Canyon is a stylized bighorn sheep or rabbit. An alleged dinosaur cave painting in Tanzania is an obvious giraffe. Three alleged cave paintings of long-necked dinosaurs in Zambia have short necks and most likely represent lizards. An alleged dinosaur painting on Agawa Rock in Lake Superior Provincial Park, Ottawa, represents Underwater Panther,a supernatural lake guardian of Ojibwe tradition. An alleged pterosaur painting at Alton, Illinois, is the product of the imagination of a nineteenth-century American author. These pieces of rock art now join the ever-growing pile of discredited “evidence”for the ancient coexistence of humans and dinosaurs
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Philip J. SenterUsing creation science to demonstrate evolution 2: morphological continuity within Dinosauriahttp://digitalcommons.uncfsu.edu/bio_wp/1
http://digitalcommons.uncfsu.edu/bio_wp/1Tue, 18 Sep 2012 12:15:11 PDT
Creationist literature claims that sufficient gaps in morphological continuity exist to classify dinosaurs into several distinct baramins (‘created kinds’). Here, I apply the baraminological method called taxon correlation to test for morphological continuity within and between dinosaurian taxa. The results show enough morphological continuity within Dinosauria to consider most dinosaurs genetically related, even by this creationist standard. A continuous morphological spectrum unites the basal members of Saurischia, Theropoda, Sauropodomorpha, Ornithischia, Thyreophora, arginocephalia, and Ornithopoda with Nodosauridae and Pachycephalosauria and with the basal ornithodirans Silesaurus and Marasuchus. Morphological gaps in the known fossil record separate only seven groups from the rest of Dinosauria. Those groups are Therizinosauroidea + Oviraptorosauria + Paraves, Tazoudasaurus + Eusauropoda, Ankylosauridae, Stegosauria, Neoceratopsia, basal Hadrosauriformes and Hadrosauridae. Each of these seven groups exhibits within-group morphological continuity, indicating common descent for all the group’s members, even according to this creationist standard.
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Philip J. Senter